libstdc++
ext/iterator
1 // HP/SGI iterator extensions -*- C++ -*-
2 
3 // Copyright (C) 2001, 2002, 2004, 2005, 2009 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /*
26  *
27  * Copyright (c) 1994
28  * Hewlett-Packard Company
29  *
30  * Permission to use, copy, modify, distribute and sell this software
31  * and its documentation for any purpose is hereby granted without fee,
32  * provided that the above copyright notice appear in all copies and
33  * that both that copyright notice and this permission notice appear
34  * in supporting documentation. Hewlett-Packard Company makes no
35  * representations about the suitability of this software for any
36  * purpose. It is provided "as is" without express or implied warranty.
37  *
38  *
39  * Copyright (c) 1996-1998
40  * Silicon Graphics Computer Systems, Inc.
41  *
42  * Permission to use, copy, modify, distribute and sell this software
43  * and its documentation for any purpose is hereby granted without fee,
44  * provided that the above copyright notice appear in all copies and
45  * that both that copyright notice and this permission notice appear
46  * in supporting documentation. Silicon Graphics makes no
47  * representations about the suitability of this software for any
48  * purpose. It is provided "as is" without express or implied warranty.
49  */
50 
51 /** @file ext/iterator
52  * This file is a GNU extension to the Standard C++ Library (possibly
53  * containing extensions from the HP/SGI STL subset).
54  */
55 
56 #ifndef _EXT_ITERATOR
57 #define _EXT_ITERATOR 1
58 
59 #pragma GCC system_header
60 
61 #include <bits/concept_check.h>
62 #include <iterator>
63 
64 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
65 
66  // There are two signatures for distance. In addition to the one
67  // taking two iterators and returning a result, there is another
68  // taking two iterators and a reference-to-result variable, and
69  // returning nothing. The latter seems to be an SGI extension.
70  // -- pedwards
71  template<typename _InputIterator, typename _Distance>
72  inline void
73  __distance(_InputIterator __first, _InputIterator __last,
74  _Distance& __n, std::input_iterator_tag)
75  {
76  // concept requirements
77  __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
78  while (__first != __last)
79  {
80  ++__first;
81  ++__n;
82  }
83  }
84 
85  template<typename _RandomAccessIterator, typename _Distance>
86  inline void
87  __distance(_RandomAccessIterator __first, _RandomAccessIterator __last,
88  _Distance& __n, std::random_access_iterator_tag)
89  {
90  // concept requirements
91  __glibcxx_function_requires(_RandomAccessIteratorConcept<
92  _RandomAccessIterator>)
93  __n += __last - __first;
94  }
95 
96  /**
97  * This is an SGI extension.
98  * @ingroup SGIextensions
99  * @doctodo
100  */
101  template<typename _InputIterator, typename _Distance>
102  inline void
103  distance(_InputIterator __first, _InputIterator __last,
104  _Distance& __n)
105  {
106  // concept requirements -- taken care of in __distance
107  __distance(__first, __last, __n, std::__iterator_category(__first));
108  }
109 
110 _GLIBCXX_END_NAMESPACE
111 
112 #endif
113